Question

The magnetic field of an electromagnetic wave is given by $B_{y}=3 \times 10^{-7} \sin \left(10^{3} x+6.28 \times 10^{12}\, t\right)$ The wavelength of the electromagnetic wave is

• A. 6.28 cm
• B. 3.14 cm
• C. 0.63 cm
• D. 0.32 cm

Answer 1

Answer: (C)

Comparing the given equation with
$B_{y}=B_{0} \sin (k x+\omega t)$
We get, $k=10^{3}$ or $\frac{2 \pi}{\lambda}=10^{3}$
$\therefore \lambda=\frac{2 \pi}{10^{3}} m =6.28 \times 10^{-3} \,m $
$=0.63\, cm$